GPU Pro 5

4. Two-Level Constraint Solver and Pipelined Local Batching for Rigid Body Simulation on GPUs 461

A measure of performance of a constraint solver is the total number of batches

created by a batching method. As the number of batches increases, the number

of serial computations and synchronization increases, which results in longer con-

straint solving time. When a rigid body in the simulation is connected by n

constraints, at least n batches are necessary to batch these constraints because

all of them must be executed in different batches. Thus, the number of batches

created by global batching is more than n

global

max

=max(n

0

,n

1

, ···,n

m

) for a sim-

ulation ...